MORBIDITY OF
ENDOTRACHEAL INTUBATION AND TRACHEOSTOMY
Nasotracheal tubes may be more easily inserted, less easily dislodged, and sometimes better tolerated than orotracheal tubes. However, they can cause nasal necrosis and maxillary sinusitis. “Blind insertion” may result in vocal cord trauma, which can be minimized by visualization, as with oral intubation. Nasotracheal tubes have small lumina, making suctioning and weaning from mechanical ventilation difficult. Orotracheal tubes are larger and more readily permit suctioning or bronchoscopy than nasotracheal tubes. However, they are less comfortable, more easily dislodged, and can be kinked or damaged by the patient’s teeth.
Complications of intubation are caused by the
pharmacologic and physiologic effects of medications and manipulation of the
upper airway as well as mechanical injury from the laryngoscope, endotracheal
tube, or stylet. Mechanical complications may include nasal, dental, or
oropharyngeal trauma. Laryngospasm, laryngeal edema, aspiration of gastric
contents, and intubation of the esophagus or right main bronchus may also
occur. Additionally, tracheal injury, including rupture from the stylet may
also be seen and is typically found at the junction of the posterior membrane
with the cartilaginous trachea.
During mechanical ventilation, several problems may
occur. Obstruction of the tube can be secondary to kinking, mucus
plugging, blood clots, or slippage or overinflation of the cuff over the end of
the tube. Cuff leaks caused by rupture may also occur, resulting in
decreased minute ventilation and aspiration of secretions.
A serious complication of both tracheostomy and
endotracheal intubation is the development of a tracheoesophageal fistula. A
fistula should be suspected when air leaks, aspiration of saliva or secretions,
or any signs of respiratory distress are noted. The diagnosis may be confirmed
by bronchoscopy. The presence of a nasogastric tube may predispose to fistula
formation caused by pressure necrosis between the trachea and esophagus.
Although occurring in fewer than 1% of patients with
tracheostomy tubes, tracheoinnominate fistula may also occur; when untreated, it
is associated with a mortality of 100%. The innominate artery typically
traverses the trachea at the level of the ninth tracheal ring, although it may
also do so between the sixth and thirteenth rings. Patients often present with
peristomal bleeding or hemoptysis, which can be mild, moderate, or severe. If
suspected, an emergent surgical consultation is required. Acute and chronic
problems may occur after extubation. An immediate complication is
laryngospasm, which may require reintubation or tracheostomy. Minor problems
such as sore throat and temporary hoarseness are frequent. Chronic problems
include vocal cord incompetence, polyps, or ulcerations and development of a
subglottic or tracheal stenosis or tracheomalacia. These can be diagnosed by indirect
laryngoscopy or bronchoscopy. Common sites for stenosis and malacia include the
area occupied by the cuff or tip of the endotracheal or tracheostomy tube as
well as the superior tracheostomy stoma.
Bleeding and subcutaneous emphysema are more or less unique to tracheostomy. Bleeding at the incision site may be obvious or may occur internally with aspiration of blood. If the tracheostomy tube becomes dislodged, reinsertion is sometimes difficult, especially with a fresh tracheostomy. If a dislodged tracheostomy tube cannot be quickly and easily reinserted, endotracheal intubation or ventilation by mask may be required until an experienced surgeon is available. If a tracheostomy tube is inadvertently removed before the formation of a stoma (7-10 days after placement), replacement should not be attempted unless the airway is secured initially with an endotracheal tube.
